Hybrid maize plant and seed (3730)

ABSTRACT

According to the invention, there is provided a hybrid maize plant, designated as 3730, produced by crossing two Pioneer Hi-Bred International, Inc. proprietary inbred maize lines. This invention relates to the hybrid seed 3730, the hybrid plant produced from the seed, and variants, mutants, and trivial modifications of hybrid 3730.

CROSS REFERENCE TO RELATED APPLICATION

This is a continuation of application Ser. No. 08/398,481, filed Mar. 3,1995, now abandoned.

FIELD OF THE INVENTION

This invention is in the field of maize breeding, specifically relatingto a hybrid maize line designated 3730.

BACKGROUND OF THE INVENTION Plant Breeding

Field crops are bred through techniques that take advantage of theplant's method of pollination. A plant is self-pollinated if pollen fromone flower is transferred to the same or another flower of the sameplant. A plant is cross-pollinated if the pollen comes from a flower ona different plant.

Plants that have been self-pollinated and selected for type for manygenerations become homozygous at almost all gene loci and produce auniform population of true breeding progeny. A cross between twodifferent homozygous lines produces a uniform population of hybridplants that may be heterozygous for many gene loci. A cross of twoplants each heterozygous at a number of gene loci will produce apopulation of hybrid plants that differ genetically and will not beuniform.

Maize (Zea mays L.), often referred to as corn in the United States, canbe bred by both self-pollination and cross-pollination techniques. Maizehas separate male and female flowers on the same plant, located on thetassel and the ear, respectively. Natural pollination occurs in maizewhen wind blows pollen from the tassels to the silks that protrude fromthe tops of the ears.

The development of a hybrid maize variety involves three steps: (1) theselection of plants from various germplasm pools for initial breedingcrosses; (2) the selfing of the selected plants from the breedingcrosses for several generations to produce a series of inbred lines,which, although different from each other, breed true and are highlyuniform; and (3) crossing the selected inbred lines with unrelatedinbred lines to produce the hybrid progeny (F₁). During the inbreedingprocess in maize, the vigor of the lines decreases. Vigor is restoredwhen two different inbred lines are crossed to produce the hybridprogeny (F₁). An important consequence of the homozygosity andhomogeneity of the inbred lines is that the hybrid created by crossing adefined pair of inbreds will always be the same. Once the inbreds thatcreate a superior hybrid have been identified, a continual supply of thehybrid seed can be produced using these inbred parents and the hybridcorn plants can then be generated from this hybrid seed supply.

Large scale commercial maize hybrid production, as it is practicedtoday, requires the use of some form of male sterility system whichcontrols or inactivates male fertility. A reliable method of controllingmale fertility in plants also offers the opportunity for improved plantbreeding. This is especially true for development of maize hybrids,which relies upon some sort of male sterility system. There are severaloptions for controlling male fertility available to breeders, such as:manual or mechanical emasculation (or detasseling), cytoplasmic malesterility, genetic male sterility, gametocides and the like.

Hybrid maize seed is typically produced by a male sterility systemincorporating manual or mechanical detasseling. Alternate strips of twoinbred varieties of maize are planted in a field, and the pollen-bearingtassels are removed from one of the inbreds (female). Providing thatthere is sufficient isolation from sources of foreign maize pollen, theears of the detasseled inbred will be fertilized only from the otherinbred (male), and the resulting seed is therefore hybrid and will formhybrid plants.

The laborious, and occasionally unreliable, detasseling process can beavoided by using cytoplasmic male-sterile (CMS) inbreds. Plants of a CMSinbred are male sterile as a result of factors resulting from thecytoplasmic, as opposed to the nuclear, genome. Thus, thischaracteristic is inherited exclusively through the female parent inmaize plants, since only the female provides cytoplasm to the fertilizedseed. CMS plants are fertilized with pollen from another inbred that isnot male-sterile. Pollen from the second inbred may or may notcontribute genes that make the hybrid plants male-fertile. Usually seedfrom detasseled fertile maize and CMS produced seed of the same hybridare blended to insure that adequate pollen loads are available forfertilization when the hybrid plants are grown.

There are several methods of conferring genetic male sterilityavailable, such as multiple mutant genes at separate locations withinthe genome that confer male sterility, as disclosed in U.S. Pat. Nos.4,654,465 and 4,727,219 to Brat et al. and chromosomal translocations asdescribed by Patterson in U.S. Pat. Nos. 3,861,709 and 3,710,511. Theseand all patents referred to are incorporated by reference. In additionto these methods, Albertsen et al., of Pioneer Hi-Bred, U.S. patentapplication Ser. No. 07/848,433, have developed a system of nuclear malesterility which includes: identifying a gene which is critical to malefertility; silencing this native gene which is critical to malefertility; removing the native promoter from the essential malefertility gene and replacing it with an inducible promoter; insertingthis genetically engineered gene back into the plant; and thus creatinga plant that is male sterile because the inducible promoter is not "on"resulting in the male fertility gene not being transcribed. Fertility isrestored by inducing, or turning "on", the promoter, which in turnallows the gene that confers male fertility to be transcribed.

There are many other methods of conferring genetic male sterility in theart, each with its own benefits and drawbacks. These methods use avariety of approaches such as delivering into the plant a gene encodinga cytotoxic substance associated with a male tissue specific promoter oran antisense system in which a gene critical to fertility is identifiedand an antisense to that gene is inserted in the plant (see:Fabinjanski, et al. EPO 89/3010153.8 publication no. 329,308 and PCTapplication PCT/CA90/00037 published as WO 90/08828).

Another system useful in controlling male sterility makes use ofgametocides. Gametocides are not a genetic system, but rather a topicalapplication of chemicals. These chemicals affect cells that are criticalto male fertility. The application of these chemicals affects fertilityin the plants only for the growing season in which the gametocide isapplied (see Carlson, Glenn R., U.S. Pat. No. 4,936,904). Application ofthe gametocide, timing of the application and genotype specificity oftenlimit the usefulness of the approach.

The use of male sterile inbreds is but one factor in the production ofmaize hybrids. The development of maize hybrids requires, in general,the development of homozygous inbred lines, the crossing of these lines,and the evaluation of the crosses. Breeding programs combine the geneticbackgrounds from two or more inbred lines or various other broad-basedsources into breeding pools from which new inbred lines are developed byselfing and selection of desired phenotypes. The new inbreds are crossedwith other inbred lines and the hybrids from these crosses are evaluatedto determine which of those have commercial potential.

There are many important factors to be considered in the art of plantbreeding, such as the ability to recognize important morphological andphysiological characteristics, the ability to design evaluationtechniques for genotypic and phenotypic traits of interest, and theability to search out and exploit the genes for the desired traits innew or improved combinations.

The objective of commercial maize hybrid line development programs is todevelop new inbred lines to produce hybrids that combine to produce highgrain yields and superior agronomic performance. The primary traitbreeders seek is yield. However, many other major agronomic traits areof importance in hybrid combination and have an impact on yield orotherwise provide superior performance in hybrid combinations. Suchtraits include percent grain moisture at harvest, relative maturity,resistance to stalk breakage, resistance to root lodging, grain quality,and disease and insect resistance. In addition, the lines per se musthave acceptable performance for parental traits such as seed yields,kernel sizes, pollen production, all of which affect ability to provideparental lines in sufficient quantity and quality for hybridization.These traits have been shown to be under genetic control and many if notall of the traits are affected by multiple genes.

Pedigree Breeding

The pedigree method of breeding is the mostly widely used methodologyfor new hybrid line development.

In general terms this procedure consists of crossing two inbred lines toproduce the non-segregating F₁ generation, and self pollination of theF₁ generation to produce the F₂ generation that segregates for allfactors for which the inbred parents differ. An example of this processis set forth below. Variations of this generalized pedigree method areused, but all these variations produce a segregating generation whichcontains a range of variation for the traits of interest.

EXAMPLE 1 Hypothetical Example of Pedigree Breeding Program

Consider a cross between two inbred lines that differ for alleles atfive loci. The parental genotypes are:

Parent 1 A b C d e F/A b C d e F

Parent 2 a B c D E f/a B c D E f

the F₁ from a cross between these two parents is:

F₁ A b C d e F/a B c D E f

Selling F₁ will produce an F₂ generation including the followinggenotypes:

    ______________________________________                                                  A B c D E f/a b C d e F                                                       A B c D e f/a b C d E F                                                       A B c D e f/a b C d e F                                             ______________________________________                                    

The number of genotypes in the F₂ is 3⁶ for six segregating loci (729)and will produce (2⁶)-2 possible new inbreds, (62 for six segregatingloci).

Each inbred parent which is used in breeding crosses represents a uniquecombination of genes, and the combined effects of the genes define theperformance of the inbred and its performance in hybrid combination.There is published evidence (Smith, O. S., J. S. C. Smith, S. L. Bowen,R,.A. Tenborg and S. J. Wall, TAG 80:833-840 (1990)) that each of thelines are different and can be uniquely identified on the basis ofgenetically-controlled molecular markers.

It has been shown (Hallauer, Arnel R. and Miranda, J. B. Fo.Quantitative Genetics in Maize Breeding, Iowa State University Press,Ames Iowa, 1981) that most traits of economic value in maize are underthe genetic control of multiple genetic loci, and that there are a largenumber of unique combinations of these genes present in elite maizegermplasm. If not, genetic progress using elite inbred lines would nolonger be possible. Studies by Duvick and Russell (Duvick, D. N.,Maydica 37:69-79, (1992); Russell, W. A., Maydica XXIX:375-390 (1983))have shown that over the last 50 years the rate of genetic progress incommercial hybrids has been between one and two percent per year.

The number of genes affecting the trait of primary economic importancein maize, grain yield, has been estimated to be in the range of 10-1000.Inbred lines which are used as parents for breeding crosses differ inthe number and combination of these genes. These factors make the plantbreeders task more difficult. Compounding this is evidence that no oneline contains the favorable allele at all loci, and that differentalleles have different economic values depending on the geneticbackground and field environment in which the hybrid is grown. Fiftyyears of breeding experience suggests that there are many genesaffecting grain yield and each of these has a relatively small effect onthis trait. The effects are small compared to breeders ability tomeasure grain yield differences in evaluation trials. Therefore, theparents of the breeding cross must differ at several of these loci sothat the genetic differences in the progeny will be large enough thatbreeders can develop a line that increases the economic worth of itshybrids over that of hybrids made with either parent.

If the number of loci segregating in a cross between two inbred lines isn, the number of unique genotypes in the F₂ generation is 3^(n) and thenumber of unique inbred lines from this cross is {(2^(n))-2}. Only avery limited number of these combinations are useful. Only about 1 in10,000 of the progeny from F₂ 's are commercially useful.

By way of example, if it is assumed that the number of segregating lociin F₂ is somewhere between 20 and 50, and that each parent is fixed forhalf the favorable alleles, it is then possible to calculate theapproximate probabilities of finding an inbred that has the favorableallele at {(n/2)+m} loci, where n/2 is the number of favorable allelesin each of the parents and m is the number of additional favorablealleles in the new inbred. See Example 2 below. The number m is assumedto be greater than three because each allele has so small an effect thatevaluation techniques are not sensitive enough to detect differences dueto three or less favorable alleles. The probabilities in Example 2 areon the order of 10⁻⁵ or smaller and they are the probabilities that atleast one genotype with (n/2)=m favorable alleles will exist.

To put this in perspective, the number of plants grown on 60 millionacres (approximate United States corn acreage) at 25,000 plants/acre is1.5×10¹².

EXAMPLE 2 Probability of Finding an Inbred with m of n Favorable Alleles

Assume each parent has n/2 of the favorable alleles and only 1/2 of thecombinations of loci are economically useful.

    ______________________________________                                        No. of  No. of favorable                                                                          No. additional                                            segregating                                                                           alleles in Parents                                                                        favorable alleles in                                                                       Probability that                             loci (n)                                                                              (n/2)       new inbred   genotype occurs*                             ______________________________________                                        20      10          14           3 × 10.sup.-5                          24      12          16           2 × 10.sup.-5                          28      14          18           1 × 10.sup.-6                          32      16          20           8 × 10.sup.-6                          36      18          22           5 × 10.sup.-6                          40      20          24           3 × 10.sup.-6                          44      22          26           2 × 10.sup.-6                          48      24          28           1 × 10.sup.-6                          ______________________________________                                         *Probability that a useful combination exists, does not include the           probability of identifying this combination if it does exist.            

The possibility of having a usably high probability of being able toidentify this genotype based on replicated field testing would be mostlikely smaller than this, and is a function of how large a population ofgenotypes is tested and how testing resources are allocated in thetesting program.

Pioneer research station staff propose about 400 to 500 new inbreds eachyear from over 2,000,000 pollinations. Of those proposed new inbreds,less than 50, and more commonly less than 30, are actually selected forcommercial use.

SUMMARY OF THE INVENTION

According to the invention, there is provided a hybrid maize plant,designated as 3730, produced by crossing two Pioneer Hi-BredInternational, Inc proprietary inbred maize lines. This invention thusrelates to the hybrid seed 3730, the hybrid plant produced from theseed, and variants, mutants, and trivial modifications of hybrid 3730.This hybrid maize plant is characterized by high yield, strong stalks,excellent early season growth and rapid dry-down after reachingmaturity. It is best adapted for the North Central Region of the UnitedStates.

DEFINITIONS

In the description and examples that follow, a number of terms are usedherein. In order to provide a clear and consistent understanding of thespecification and claims, including the scope to be given such terms,the following definitions are provided. NOTE: ABS is in absolute termsand %MN is percent of the mean for the experiments in which the inbredor hybrid was grown. These designators will follow the descriptors todenote how the values are to be interpreted. Below are the descriptorsused in the data tables included herein.

ANT ROT=ANTHRACNOSE STALK ROT (Colletotrichum graminicola), A 1 to 9visual rating indicating the resistance to Anthracnose Stalk Rot. Ahigher score indicates a higher resistance.

BAR PLT=BARREN PLANTS. The percent of plants per plot that were notbarren (lack ears).

BRT STK=BRITTLE STALKS. This is a measure of the stalk breakage near thetime of pollination, and is an indication of whether a hybrid or inbredwould snap or break near the time of flowering under severe winds. Dataare presented as percentage of plants that did not snap in pairedcomparisons and on a 1 to 9 scale (9=highest resistance) inCharacteristics Charts.

BU ACR=YIELD (BUSHELS/ACRE). Yield of the grain at harvest in bushelsper acre adjusted to 15.5% moisture.

CLN=CORN LETHAL NECROSIS (synergistic interaction of maize chloroticmottle virus (MCMV) in combination with either maize dwarf mosaic virus(MDMV-A or MDMV-B) or wheat streak mosaic virus (WSMV)). A 1 to 9 visualrating indicating the resistance to Corn Lethal Necrosis. A higher scoreindicates a higher resistance.

COM RST=COMMON RUST (Puccinia sorghum). A 1 to 9 visual ratingindicating the resistance to Common Rust. A higher score indicates ahigher resistance.

CRM=COMPARATIVE RELATIVE MATURITY (see PRM).

D/D=DRYDOWN. This represents the relative rate at which a hybrid willreach acceptable harvest moisture compared to other hybrids on a 1-9rating scale. A high score indicates a hybrid that dries relatively fastwhile a low score indicates a hybrid that dries slowly.

D/E=DROPPED EARS. Represented in a 1 to 9 scale in the CharacteristicsChart, where 9 is the rating representing the least, or no, droppedears.

DIP ERS=DIPLODIA EAR MOLD SCORES (Diplodia maydis and Diplodiamacrospora). A 1 to 9 visual rating indicating the resistance toDiplodia Ear Mold. A higher score indicates a higher resistance.

DRP EAR=DROPPED EARS. A measure of the number of dropped ears per plotand represents the percentage of plants that did not drop ears prior toharvest.

D/T=DROUGHT TOLERANCE. This represents a 1-9 rating for droughttolerance, and is based on data obtained under stress conditions. A highscore indicates good drought tolerance and a low score indicates poordrought tolerance.

EAR HT=EAR HEIGHT. The ear height is a measure from the ground to thehighest placed developed ear node attachment and is measured in inches.This is represented in a 1 to 9 scale in the Characteristics Chart,where 9 is highest.

EAR MLD=General Ear Mold. Visual rating (1-9 score) where a "1" is verysusceptible and a "9" is very resistant. This is based on overall ratingfor ear mold of mature ears without determining the specific moldorganism, and may not be predictive for a specific ear mold.

EAR SZ=EAR SIZE. A 1 to 9 visual rating of ear size. The higher therating the larger the ear size.

ECB 1LF=EUROPEAN CORN BORER FIRST GENERATION LEAF FEEDING (Ostrinianubilalis). A 1 to 9 visual rating indicating the resistance topreflowering leaf feeding by first generation European Corn Borer. Ahigher score indicates a higher resistance.

ECB 2IT=EUROPEAN CORN BORER SECOND GENERATION INCHES OF TUNNELING(Ostrinia nubilalis). Average inches of tunneling per plant in thestalk.

ECB 2SC=EUROPEAN CORN BORER SECOND GENERATION (Ostrinia nubilalis). A 1to 9 visual rating indicating post flowering degree of stalk breakageand other evidence of feeding by European Corn Borer, Second Generation.A higher score indicates a higher resistance.

ECB DPE=EUROPEAN CORN BORER DROPPED EARS (Ostrinia nubilalis). Droppedears due to European Corn Borer. Percentage of plants that did not dropears under second generation corn borer infestation.

E/G=EARLY GROWTH. This represents a 1 to 9 rating for early growth,scored when two leaf collars are visible.

EST CNT=EARLY STAND COUNT. This is a measure of the stand establishmentin the spring and represents the number of plants that emerge on perplot basis for the inbred or hybrid.

EYE SPT=Eye Spot (Kabatiella zeae or Aureobasidium zeae). A 1 to 9visual rating indicating the resistance to Eye Spot. A higher scoreindicates a higher resistance.

FUS ERS=FUSARIUM EAR ROT SCORE (Fusariurn moniliforme or Fusariumsubglutinans). A 1 to 9 visual rating indicating the resistance toFusarium ear rot. A higher score indicates a higher resistance.

G/A=GRAIN APPEARANCE. Appearance of grain in the grain tank (scored downfor mold, cracks, read streak, etc.).

GDU=Growing Degree Units. Using the Barger Heat Unit Theory, thatassumes that maize growth occurs in the temperature range 50° F.-86° F.and that temperatures outside this range slow down growth; the maximumdaily heat unit accumulation is 36 and the minimum daily heat unitaccumulation is 0. The seasonal accumulation of GDU is a major factor indetermining maturity zones.

GDU PHY=GDU TO PHYSIOLOGICAL MATURITY. The number of growing degreeunits required for an inbred or hybrid line to have approximately 50percent of plants at physiological maturity from time of planting.Growing degree units are calculated by the Barger method.

GDU SHD=GDU TO SHED. The number of growing degree units (GDUs) or heatunits required for an inbred line or hybrid to have approximately 50percent of the plants shedding pollen and is measured from the time ofplanting. Growing degree units are calculated by the Barger Method,where the heat units for a 24-hour period are: ##EQU1##

The highest maximum temperature used is 86° F. and the lowest minimumtemperature used is 50° F. For each inbred or hybrid it takes a certainnumber of GDUs to reach various stages of plant development.

GDU SLK=GDU TO SILK. The number of growing degree units required for aninbred line or hybrid to have approximately 50 percent of the plantswith silk emergence from time of planting. Growing degree units arecalculated by the Barger Method as given in GDU SHD definition.

GIB ERS=GIBBERELLA EAR ROT (PINK MOLD) (Gibberella zeae). A 1 to 9visual rating indicating the resistance to Gibberella Ear Rot. A higherscore indicates a higher resistance.

GLF SPT=Gray Leaf Spot (Cercospora zeae-maydis). A 1 to 9 visual ratingindicating the resistance to Gray Leaf Spot. A higher score indicates ahigher resistance.

GOS WLT=Goss' Wilt (Corynebacteriurn nebraskense). A 1 to 9 visualrating indicating the resistance to Goss' Wilt. A higher score indicatesa higher resistance.

GRN APP=GRAIN APPEARANCE. This is a 1 to 9 rating for the generalappearance of the shelled grain as it is harvested based on such factorsas the color of harvested grain, any mold on the grain, and any crackedgrain. High scores indicate good grain quality.

H/POP=YIELD AT HIGH DENSITY. Yield ability at relatively high plantdensities on 1-9 relative rating system with a higher number indicatingthe hybrid responds well to high plant densities for yield relative toother hybrids. A 1, 5, and 9 would represent very poor, average, andvery good yield response, respectively, to increased plant density.

HC BLT=HELMINTHOSPORIUM CARBONUM LEAF BLIGHT (Helminthosporiumcarbonum). A 1 to 9 visual rating indicating the resistance toHelminthosporium infection. A higher score indicates a higherresistance.

HD SMT=HEAD SMUT (Sphacelotheca reiliana). This score indicates thepercentage of plants not infected.

INC D/A=GROSS INCOME (DOLLARS PER ACRE). Relative income per acreassuming drying costs of two cents per point above 15.5 percent harvestmoisture and current market price per bushel.

INCOME/ACRE. Income advantage of hybrid to be patented over other hybridon per acre basis.

INC ADV=GROSS INCOME ADVANTAGE, GROSS INCOME advantage of variety #1over variety #2.

L/POP=YIELD AT LOW DENSITY. Yield ability at relatively low plantdensities on a 1-9 relative system with a higher number indicating thehybrid responds well to low plant densities for yield relative to otherhybrids. A 1, 5, and 9 would represent very poor, average, and very goodyield response, respectively, to low plant density.

MDM CPX=MAIZE DWARF MOSAIC COMPLEX (MDMV=Maize Dwarf Mosaic Virus andMCDV=Maize Chlorotic Dwarf Virus). A 1 to 9 visual rating indicating theresistance to Maize Dwarf Mosaic Complex. A higher score indicates ahigher resistance.

MST=HARVEST MOISTURE. The moisture is the actual percentage moisture ofthe grain at harvest.

MST ADV=MOISTURE ADVANTAGE. The moisture advantage of variety #1 overvariety #2 as calculated by: MOISTURE of variety #2--MOISTURE of variety#1=MOISTURE ADVANTAGE of variety #1.

NLF BLT=Northern Leaf Blight (Helminthosporiurn turcicum or Exserohilumturcicum). A 1 to 9 visual rating indicating the resistance to NorthernLeaf Blight. A higher score indicates a higher resistance.

PHY CRM=CRM at physiological maturity.

PLT HT=PLANT HEIGHT. This is a measure of the height of the plant fromthe ground to the tip of the tassel in inches. This is represented as a1 to 9 scale, 9 highest, in the Characteristics Chart.

POL SC=POLLEN SCORE. A 1 to 9 visual rating indicating the amount ofpollen shed. The higher the score the more pollen shed.

POL WT=POLLEN WEIGHT. This is calculated by dry weight of tasselscollected as shedding commences minus dry weight from similar tasselsharvested after shedding is complete.

It should be understood that the inbred can, through routinemanipulation of cytoplasmic or other factors, be produced in amale-sterile form. Such embodiments are also contemplated within thescope of the present claims.

POP K/A=PLANT POPULATIONS. Measured as 1000s per acre.

POP ADV=PLANT POPULATION ADVANTAGE. The plant population advantage ofvariety #1 over variety #2 as calculated by PLANT POPULATION of variety#2=PLANT POPULATION of variety #1=PLANT POPULATION ADVANTAGE of variety#1.

PRM=PREDICTED Relative Maturity. This trait, predicted relativematurity, is based on the harvest moisture of the grain. The relativematurity rating is based on a known set of checks and utilizes standardlinear regression analyses and is referred to as the ComparativeRelative Maturity Rating System that is similar to the MinnesotaRelative Maturity Rating System.

PRM SHD=A relative measure of the growing degree units (GDU) required toreach 50% pollen shed. Relative values are predicted values from thelinear regression of observed GDU's on relative maturity of commercialchecks.

PRO=PROTEIN RATING. Rating on a 1 to 9 scale comparing relative amountof protein in the grain compared to hybrids of similar maturity. A "1"score difference represents a 0.4 point change in grain protein percent(e.g., 8.0% to 8.4%).

P/Y=PROTEIN/YIELD RATING. Indicates, on a 1 to 9 scale, the economicvalue of a hybrid for swine and poultry feeders. This takes into accountthe income due to yield, moisture and protein content.

ROOTS (%)=Percent of stalks NOT root lodged at harvest.

R/L=ROOT LODGING. A 1 to 9 rating indicating the level of root lodgingresistance. The higher score represents higher levels of resistance.

RT LDG=ROOT LODGING. Root lodging is the percentage of plants that donot root lodge; plants that lean from the vertical axis as anapproximately 30° angle or greater would be counted as root lodged.

RTL ADV=ROOT LODGING ADVANTAGE. The root lodging advantage of variety #1over variety #2.

S/L=STALK LODGING. A 1 to 9 rating indicating the level of stalk lodgingresistance. The higher scores represent higher levels of resistance.

SCT GRN=SCATTER GRAIN. A 1 to 9 visual rating indicating the amount ofscatter grain (lack of pollination or kernel abortion) on the ear. Thehigher the score the less scatter grain.

SDG VGR=SEEDLING VIGOR. This is the visual rating (1 to 9) of the amountof vegetative growth after emergence at the seedling stage(approximately five leaves). A higher score indicates better vigor.

SEL IND=SELECTION INDEX. The selection index gives a single measure ofthe hybrid's worth based on information for up to five traits. A maizebreeder may utilize his or her own set of traits for the selectionindex. One of the traits that is almost always included is yield. Theselection index data presented in the tables represent the mean valueaveraged across testing stations.

SLF BLT=SOUTHERN LEAF BLIGHT (Helminthosporium maydis or Bipolarismaydis). A 1 to 9 visual rating indicating the resistance to SouthernLeaf Blight. A higher score indicates a higher resistance.

SLK CRM=CRM at Silking.

SOU RST=SOUTHERN RUST (Puccinia polysora). A 1 to 9 visual ratingindicating the resistance to Southern Rust, A higher score indicates ahigher resistance.

STA GRN=STAYGREEN. Staygreen is the measure of plant health near thetime of black layer formation (physiological maturity). A high scoreindicates better late-season plant health.

STAND (%)=Percent of stalks standing at harvest.

STD ADV=STALK STANDING ADVANTAGE. The advantage of variety #1 overvariety #2 for the trait STK CNT.

STK CNT=NUMBER OF PLANTS. This is the final stand or number of plantsper plot.

STK LDG=STALK LODGING. This is the percentage of plants that did notstalk lodge (stalk breakage) as measured by either natural lodging orpushing the stalks and determining the percentage of plants that breakbelow the ear.

STW WLT=Stewart's Wilt (Erwinia stewartii). A 1 to 9 visual ratingindicating the resistance to Stewart's Wilt. A higher score indicates ahigher resistance.

TAS BLS=TASSEL BLAST. A 1 to 9 visual rating was used to measure thedegree of blasting (necrosis due to heat stress) of the tassel at thetime of flowering. A 1 would indicate a very high level of blasting attime of flowering, while a 9 would have no tassel blasting.

TAS SZ=TASSEL SIZE. A 1 to 9 visual rating was used to indicate therelative size of the tassel. The higher the rating the larger thetassel.

TAS WT=TASSEL WEIGHT. This is the average weight of a tassel (grams)just prior to pollen shed.

TEX EAR=EAR TEXTURE. A 1 to 9 visual rating was used to indicate therelative hardness (smoothness of crown) of mature grain. A 1 would bevery soft (extreme dent) while a 9 would be very hard (flinty or verysmooth crown).

TIL LER=TILLERS. A count of the number of tillers per plot that couldpossibly shed pollen was taken. Data is given as a percentage oftillers: number of tillers per plot divided by number of plants perplot.

TST WT (CHARACTERISTICS CHART)=Test weight on a 1 to 9 rating scale witha 9 being the highest rating.

TST WT=TEST WEIGHT (UNADJUSTED). The measure of the weight of the grainin pounds for a given volume (bushel).

TST WTA=TEST WEIGHT ADJUSTED. The measure of the weight of the grain inpounds for a given volume (bushel) adjusted for 15.5 percent moisture.

TSW ADV=TEST WEIGHT ADVANTAGE. The test weight advantage of variety #1over variety #2.

WIN M %=PERCENT MOISTURE WINS.

WIN Y %=PERCENT YIELD WINS.

YLD=YIELD. It is the same as BU ACR ABS.

YLD ADV=YIELD ADVANTAGE. The yield advantage of variety #1 over variety#2 as calculated by: YIELD of variety #1=YIELD variety #2=yieldadvantage of variety #1.

YLD SC=YIELD SCORE. A 1 to 9 visual rating was used to give a relativerating for yield based on plot ear piles. The higher the rating thegreater visual yield appearance.

DETAILED DESCRIPTION OF THE INVENTION

Pioneer Brand Hybrid 3730 is a single cross, yellow endosperm, dentmaize hybrid with high yield in its maturity. Hybrid 3730 demonstratesan unexpected, excellent early season growth that is very rapid relativeto other hybrids for its maturity. In addition, Hybrid 3730 has verygood stalks and rapid dry-down after reaching maturity. Hybrid 3730 alsodemonstrates improved staygreen over other hybrids in its maturity.

This hybrid has the following characteristics based on the datacollected primarily at Johnston, Iowa.

                  TABLE 1                                                         ______________________________________                                        VARIETY DESCRIPTION INFORMATION                                               HYBRID = PIONEER BRAND 3730                                                   Type: Dent          Region Best Adapted: North                                ______________________________________                                        A.  Minnesota Relative Maturity Rating (harvest moisture): 101                    GDU's to Physiological Maturity (black layer): 2390                           GDU's to 50% Silk: 1230                                                   B.  Plant Characteristics:                                                        Plant height (to tassel tip): 297 cm                                          Length of top ear internode: 19 cm                                            Number of ears per stalk: Single                                              Ear height (to base of top ear): 108 cm                                       Number of tillers: None                                                       Cytoplasm type: Normal                                                    C   Leaf:                                                                         Color: (B14) Dark Green*                                                      Angle from Stalk: <25 degrees                                                 Marginal Waves: (OH7L) Many                                                   Number of Leaves (mature plants): 19                                          Sheath Pubescence: (W22) Light                                                Longitudinal Creases: (OH56A) Few                                             Length (Ear node leaf): 93 cm                                                 Width (widest point, ear node leaf): 11 cm                                D.  Tassel:                                                                       Number lateral branches: 5                                                    Branch Angle from central spike: 30-40 degrees                                Pollen Shed: (KY21) Heavy                                                     Peduncle Length (top leaf to basal branches): 19 cm                           Anther Color: Pink*                                                           Glume Color: Green*                                                       E.  Ear (Husked Ear Data Except When Stated Otherwise):                           Length: 18 cm                                                                 Weight: 220 gm                                                                Mid-point Diameter: 47 mm                                                     Silk Color: Pink*                                                             Husk Extension (Harvest stage): Medium (Barely covering ear)                  Husk Leaf: Long(>15 cm)                                                       Taper of Ear: Average                                                         Position of Shank (dry husks): Upright                                        Kernel Rows: Slightly curved, Distinct Number = 14                            Husk Color (fresh): Light Green*                                              Husk Color (dry): Buff*                                                       Shank Length: 14 cm                                                           Shank (No. of internodes): 9                                              F.  Kernel (Dried).                                                               Size (from ear mid-point)                                                     Length: 14 mm                                                                 Width: 8 mm                                                                   Thick: 4 mm                                                                   Shape Grade (% rounds): 10                                                    Pericarp Color: Colorless*                                                    Aleurone Color: Homozygous Yellow*                                            Endosperm Color: Yellow*                                                      Endosperm Type: Normal                                                        Gm Wt/100 Seeds (unsized): 33 gm                                          G.  Cob:                                                                          Diameter at mid-point: 24 mm                                                  Strength: Strong                                                              Color: Red*                                                               H.  Diseases:                                                                     N. Leaf Blight (E. turcicum): Intermediate                                    Eye Spot (K. zeae): Resistant                                                 Gray Leaf Spot (C. zeae): Susceptible                                         Goss's Wilt (C. nebraskense): Resistant                                       Fusarium Ear Mold (F. moniliforme): Resistant                                 Gibberella Ear Rot (G. zeae): Intermediate                                I.  Insects:                                                                      European Corn Borer-2 (Post-flowering): Intermediate                          The above descriptions are based on a scale of 1-9, 1 being highly            susceptible 9 being highly resistant.                                         S (Susceptible): Would generally represent a score of 1-3.                    I (Intermediate): Would generally represent a score of 4-5.                   R (Resistant): Would generally represent a score of 6-7.                      H (Highly Resistant): Would generally represent a score of 8-9.               Highly resistant does not imply the inbred is immune.                     J.  Variety Most Closely Resembling;                                          Character                                                                              Hybrid                                                               Maturity Pioneer Brand 3733                                                   Usage    Pioneer Brand 3733                                                   ______________________________________                                         *In interpreting the foregoing color designations, reference may be had t     the Munsell Glossy Book of Color, a standard color reference.            

Data for Items B, C, D, E, F, and G is based primarily on a maximum oftwo reps from Johnston, Iowa grown in 1994.

Research Comparisons for Pioneer Hybrid 3730

Comparisons of characteristics for Pioneer Brand Hybrid 3730 were madeagainst Pioneer Brand Hybrids 3723, 3733, 3714 and 3563. Table 2Acompares Pioneer Brand Hybrid 3730 and Pioneer Brand Hybrid 3723. Theresults show Hybrid 3730 is significantly higher yielding than Hybrid3723. In addition, Hybrid 3730 has a higher seedling vigor score and ahigher early stand count than Hybrid 3723.

Table 2B compares Pioneer Hybrid 3730 and Pioneer Hybrid 3733. Theresults show Hybrid 3730 is significantly higher yielding than Hybrid3733. In addition, Hybrid 3730 has a significantly higher seedling vigorscore and a significantly higher resistance to stalk lodging than Hybrid3733.

Table 2C compares Pioneer Hybrid 3730 and Pioneer Hybrid 3714. Theresults show the hybrids to have similar yields. Hybrid 3730 has tallerplants than Hybrid 3714.

Table 2D compares Pioneer Hybrid 3730 and Pioneer Hybrid 3563. Theresults show Hybrid 3730 is higher yielding with higher seedling vigorthan Hybrid 3563.

                                      TABLE 2A                                    __________________________________________________________________________    PAIRED COMPARISON REPORT                                                      VARIETY #1 = 3730                                                             VARIETY #2 = 3723                                                             * = 10% SIG + = 5% SIG # = 1% S1G                                             __________________________________________________________________________               BU BU  MST TST                                                                              SDG EST                                                                              TIL GDU                                              VAR ACR                                                                              ACR     WT VGR CNT                                                                              LER SHD                                              #   ABS                                                                              % MN                                                                              ABS ABS                                                                              ABS ABS                                                                              ABS ABS                                       __________________________________________________________________________    TOTAL SUM                                                                            1   154.7                                                                            106 26.6                                                                              53.1                                                                             7.1 62.7                                                                             3.8 101.8                                            2   143.6                                                                            97  25.6                                                                              52.9                                                                             5.0 59.6                                                                             2.9 102.8                                            LOCS                                                                              55 55  56  42 36  31 5   18                                               REPS                                                                              75 75  76  53 49  38 10  28                                               DIFF                                                                              11.1                                                                             8   1.0 0.2                                                                              2.1 3.1                                                                              0.9 1.0                                              PROB                                                                              .000#                                                                            .000#                                                                             .000#                                                                             .329                                                                             .000#                                                                             .006#                                                                            .375                                                                              .127                                      __________________________________________________________________________               GDU                                                                              PLT EAR RT STA STK                                                                              BRT GRN                                              VAR SLK                                                                              HT  HT  LDG                                                                              GRN LDG                                                                              STK APP                                              #   ABS                                                                              ABS ABS ABS                                                                              ABS ABS                                                                              ABS ABS                                       __________________________________________________________________________    TOTAL SUM                                                                            1   115.0                                                                            108.5                                                                             45.2                                                                              94.5                                                                             5.3 96.8                                                                             98.0                                                                              6.4                                              2   117.7                                                                            110.0                                                                             50.6                                                                              93.4                                                                             5.5 96.2                                                                             90.5                                                                              5.9                                              LOCS                                                                              9  33  33  23 14  48 7   19                                               REPS                                                                              13 47  47  33 24  63 11  21                                               DIFF                                                                              2.7                                                                              1.6 5.3 1.1                                                                              0.3 0.6                                                                              7.5 0.5                                              PROB                                                                              .006#                                                                            .044+                                                                             .000#                                                                             .652                                                                             .588                                                                              .506                                                                             .104                                                                              .078*                                     __________________________________________________________________________               BAR                                                                              DRP FUS EYE                                                                              ECB ECB                                                                              ECB                                                  VAR PLT                                                                              EAR ERS SPT                                                                              DPE 1LF                                                                              2SC                                                  #   ABS                                                                              ABS ABS ABS                                                                              ABS ABS                                                                              ABS                                           __________________________________________________________________________    TOTAL SUM                                                                            1   99.3                                                                             100.0                                                                             8.7 4.0                                                                              100.0                                                                             7.0                                                                              8.0                                                  2   99.4                                                                             100.0                                                                             7.8 4.0                                                                              100.0                                                                             6.0                                                                              6.0                                                  LOCS                                                                              3  26  3   1  3   1  1                                                    REPS                                                                              6  30  6   1  3   1  2                                                    DIFF                                                                              0.1                                                                              0.0 0.8 0.0                                                                              0.0 1.0                                                                              2.0                                                  PROB                                                                              .889                                                                             1.00                                                                              .038+  1.00                                                 __________________________________________________________________________

                                      TABLE 2B                                    __________________________________________________________________________    PAIRED COMPARISON REPORT                                                      VARIETY #1 = 3730                                                             VARIETY #2 = 3723                                                             * = 10% SIG + = 5% SIG # = 1% S1G                                             __________________________________________________________________________               BU BU  MST TST                                                                              SDG EST                                                                              TIL GDU                                              VAR ACR                                                                              ACR     WT VGR CNT                                                                              LER SHD                                              #   ABS                                                                              % MN                                                                              ABS ABS                                                                              ABS ABS                                                                              ABS ABS                                       __________________________________________________________________________    TOTAL SUM                                                                            1   166.4                                                                            104 25.4                                                                              53.3                                                                             6.9 57.4                                                                             5.2 122.0                                            2   158.0                                                                            99  24.9                                                                              54.9                                                                             5.3 57.4                                                                             14.1                                                                              124.9                                            LOCS                                                                              252                                                                              252 259 176                                                                              105 162                                                                              5   96                                               REPS                                                                              327                                                                              327 334 212                                                                              148 210                                                                              8   121                                              DIFF                                                                              8.4                                                                              5   0.5 1.7                                                                              1.6 0.0                                                                              8.9 2.9                                              PROB                                                                              .000#                                                                            .000#                                                                             .000#                                                                             .000#                                                                            .000#                                                                             .961                                                                             .166                                                                              .000#                                     __________________________________________________________________________               GDU                                                                              PLT EAR RT STA STK                                                                              BRT GRN                                              VAR SLK                                                                              HT  HT  LDG                                                                              GRN LDG                                                                              STK APP                                              #   ABS                                                                              ABS ABS ABS                                                                              ABS ABS                                                                              ABS ABS                                       __________________________________________________________________________    TOTAL SUM                                                                            1   121.1                                                                            108.7                                                                             43.5                                                                              91.1                                                                             4.8 97.2                                                                             96.8                                                                              6.3                                              2   124.9                                                                            106.9                                                                             45.7                                                                              92.8                                                                             5.0 90.2                                                                             99.3                                                                              6.7                                              LOCS                                                                              38 128 105 114                                                                              71  227                                                                              34  45                                               REPS                                                                              52 159 136 151                                                                              92  282                                                                              44  55                                               DIFF                                                                              3.8                                                                              1.8 2.3 1.8                                                                              0.2 7.0                                                                              2.5 0.4                                              PROB                                                                              .000#                                                                            .000#                                                                             .000#                                                                             .110                                                                             .265                                                                              .000#                                                                            .024+                                                                             .015+                                     __________________________________________________________________________               EAR                                                                              BAR DRP GLF                                                                              NLF GOS                                                                              HD  FUS                                              VAR MLD                                                                              PLT EAR SPT                                                                              BLT WLT                                                                              SMT ERS                                              #   ABS                                                                              ABS ABS ABS                                                                              ABS ABS                                                                              ABS ABS                                       __________________________________________________________________________    TOTAL SUM                                                                            1   7.5                                                                              99.3                                                                              99.9                                                                              2.8                                                                              5.3 6.5                                                                              98.7                                                                              7.7                                              2   9.0                                                                              99.7                                                                              99.8                                                                              3.5                                                                              5.1 7.0                                                                              96.5                                                                              6.8                                              LOCS                                                                              1  3   169 3  13  2  5   6                                                REPS                                                                              2  6   197 5  23  4  9   12                                               DIFF                                                                              1.5                                                                              0.4 0.1 0.7                                                                              0.2 0.5                                                                              2.2 0.9                                              PROB   .585                                                                              .051*                                                                             .184                                                                             .445                                                                              .500                                                                             .091*                                                                             .330                                      __________________________________________________________________________               GIB                                                                              EYE COM ECB                                                                              ECB ECB                                                                              ECB                                                  VAR ERS                                                                              SPT RST DPE                                                                              1LF 2SC                                                                              2IT                                                  #   ABS                                                                              ABS ABS ABS                                                                              ABS ABS                                                                              ABS                                           __________________________________________________________________________    TOTAL SUM                                                                            1   5.6                                                                              6.3 5.5 99.1                                                                             5.2 5.2                                                                              3.8                                                  2   7.2                                                                              5.5 6.5 99.1                                                                             6.1 5.4                                                                              3.7                                                  LOCS                                                                              6  29  2   13 5   13 2                                                    REPS                                                                              12 33  2   17 12  24 6                                                    DIFF                                                                              1.6                                                                              0.7 1.0 0.0                                                                              0.8 0.2                                                                              0.0                                                  PROB                                                                              .115                                                                             .008#                                                                             .000#                                                                             .969                                                                             .049+                                                                             .628                                                                             .972                                          __________________________________________________________________________

                  TABLE 2C                                                        ______________________________________                                        PAIRED COMPARISON REPORT                                                      VARIETY #1 = 3730                                                             VARIETY #2 = 3714                                                             * = 10% SIG + = 5% SIG # = 1% SIG                                             ______________________________________                                                       BU     BU    MST  SDG  TIL  GDU  PLT                                  VAR     ACR    ACR        VGR  LER  SHD  HT                                   #       ABS    % MN  ABS  ABS  ABS  ABS  ABS                           ______________________________________                                        TOTAL  1       159.0  102   17.1 8.0  4.6  77.5 112.1                         SUM    2       161.1  104   18.3 7.0  0.3  78.3 109.9                                LOCS    3      3     3    3    3    3    8                                    REPS    6      6     6    6    6    6    16                                   DIFF    2.1    1     1.2  1.0  4.3  0.8  2.2                                  PROB    .530   .541  .106 .184 .202 .338 .042+                         ______________________________________                                                       EAR    RT    STA  STK  BRT  BAR                                       VAR     HT     LDG   GRN  LDG  STK  PLT                                       #       ABS    ABS   ABS  ABS  ABS  ABS                                ______________________________________                                        TOTAL  1       41.8   98.0  6.3  99.4 92.7 99.3                               SUM    2       46.5   96.0  6.9  99.1 92.7 98.6                                      LOCS    8      3     6    3    3    3                                         REPS    16     6     12   6    3    6                                         DIFF    4.7    2.0   0.7  0.4  0.0  0.7                                       PROB    .001#  .230  .427 .709      .730                               ______________________________________                                                       NLF    FUS   ECB  ECB  ECB  ECB                                       VAR     BLT    ERS   DPE  ILF  25C  21T                                       #       ABS    ABS   ABS  ABS  ABS  ABS                                ______________________________________                                        TOTAL  1       5.0    8.7   95.0 4.8  4.7  3.8                                SUM    2       5.3    7.7   91.7 6.8  6.9  2.3                                       LOCS    3      3     2    4    5    2                                         REPS    4      6     6    11   13   6                                         DIFF    0.3    1.0   3.3  2.0  2.1  1.4                                       PROB    .742   .074* .500 .041+                                                                              .022+                                                                              .637                               ______________________________________                                    

                                      TABLE 2D                                    __________________________________________________________________________    PAIRED COMPARISON REPORT                                                      VARIETY #1 = 3730                                                             VARIETY#2 = 3563                                                              *  = 10% SIG + = 5% SIG # = 1% SIG                                            __________________________________________________________________________               BU BU  MST                                                                              TST                                                                              SDG                                                                              EST                                                                              TIL                                                                              GDU                                                                              GDU                                              VAR ACR                                                                              ACR    WT VGR                                                                              CNT                                                                              LER                                                                              SHD                                                                              SLK                                              #   ABS                                                                              % MN                                                                              ABS                                                                              ABS                                                                              ABS                                                                              ABS                                                                              ABS                                                                              ABS                                                                              ABS                                       __________________________________________________________________________    TOTAL SUM                                                                            1   159.6                                                                            103 24.1                                                                             54.0                                                                             6.8                                                                              57.6                                                                             6.1                                                                              121.9                                                                            121.6                                            2   153.5                                                                            98  25.6                                                                             54.5                                                                             5.3                                                                              58.4                                                                             1.0                                                                              128.3                                                                            130.1                                            LOCS                                                                              133                                                                              133 136                                                                              105                                                                              71 103                                                                              2  41 26                                               REPS                                                                              209                                                                              209 214                                                                              149                                                                              95 145                                                                              2  52 34                                               DIFF                                                                              6.0                                                                              5   1.5                                                                              0.5                                                                              1.5                                                                              0.8                                                                              5.1                                                                              6.4                                                                              8.4                                              PROB                                                                              .000#                                                                            .000#                                                                             .000#                                                                            .000#                                                                            .000#                                                                            .040+                                                                            .212                                                                             .000#                                                                            .000#                                     __________________________________________________________________________               PLT                                                                              EAR RT STA                                                                              STK                                                                              BRT                                                                              GRN                                                                              DRP                                                                              GLF                                              VAR HT HT  LDG                                                                              GRN                                                                              LDG                                                                              STK                                                                              APP                                                                              EAR                                                                              SPT                                              #   ABS                                                                              ABS ABS                                                                              ABS                                                                              ABS                                                                              ABS                                                                              ABS                                                                              ABS                                                                              ABS                                       __________________________________________________________________________    TOTAL SUM                                                                            1   105.2                                                                            41.7                                                                              92.2                                                                             4.6                                                                              97.1                                                                             93.2                                                                             6.2                                                                              99.9                                                                             1.0                                              2   108.3                                                                            43.3                                                                              96.0                                                                             6.6                                                                              96.1                                                                             94.8                                                                             5.8                                                                              99.9                                                                             4.0                                              LOCS                                                                              66 66  61 43 116                                                                              34 38 85 1                                                REPS                                                                              81 81  106                                                                              50 170                                                                              44 64 127                                                                              1                                                DIFF                                                                              3.0                                                                              1.6 3.8                                                                              1.9                                                                              1.0                                                                              1.6                                                                              0.4                                                                              0.0                                                                              3.0                                              PROB                                                                              .000#                                                                            .001#                                                                             .008#                                                                            .000#                                                                            .158                                                                             .178                                                                             .058*                                                                            .494                                         __________________________________________________________________________               NLF                                                                              FUS EYE                                                                              COM                                                                              ECB                                                                              ECB                                                                              ECB                                                                              ECB                                                 VAR BLT                                                                              ERS SPT                                                                              RST                                                                              DPE                                                                              1LF                                                                              25C                                                                              21T                                                 #   ABS                                                                              ABS ABS                                                                              ABS                                                                              ABS                                                                              ABS                                                                              ABS                                                                              ABS                                          __________________________________________________________________________    TOTAL SUM                                                                            1   5.4                                                                              8.0 4.8                                                                              6.0                                                                              99.1                                                                             5.2                                                                              5.0                                                                              3.8                                                 2   7.3                                                                              5.0 5.2                                                                              4.5                                                                              99.6                                                                             5.1                                                                              7.0                                                                              1.9                                                 LOCS                                                                              6  1   5  2  13 5  12 2                                                   REPS                                                                              8  1   5  2  17 12 22 6                                                   DIFF                                                                              1.8                                                                              3.0 0.4                                                                              1.5                                                                              0.5                                                                              0.2                                                                              2.0                                                                              1.9                                                 PROB                                                                              .090*  .587                                                                             .500                                                                             .342                                                                             .776                                                                             .004#                                                                            .425                                         __________________________________________________________________________

Strip Test Data for Hybrid 3730

Comparison data was collected from strip tests that were grown byfarmers. Each hybrid was grown in strips of 4, 6, 8, 12, etc. rows infields depending on the size of the planter used. The data was collectedfrom strip tests that had the hybrids in the same area and weighed. Themoisture percentage was determined and bushels per acre was adjusted to15.5 percent moisture. The number of comparisons represent the number oflocations or replications for the two hybrids that were grown in thesame field in close proximity and compared.

Comparison strip testing was done between Pioneer Brand Hybrid 3730 andPioneer Brand Hybrids 3737,3723,3733,3714 and 3563. The comparisons comefrom all the hybrid 's adapted growing areas in the United States.

These results are presented in Table 3. Hybrid 3730 has a yieldadvantage over all of the hybrids. Hybrid 3730 has an income/acreadvantage over all but one of the hybrids, 3723, which has a similarincome per acre as 3730. The income per acre advantage ranged from $3.46to $13.80. Hybrid 3730's yield and income advantage plus its advantagefor other characteristics over these hybrids will make it an importantaddition for most of the areas where these hybrids are grown.

                                      TABLE 3                                     __________________________________________________________________________    PIONEER HYBRID 3730 VS. PIONEER HYBRIDS 3737, 3723, 3733, 3714 and 3563       FROM 1994 STRIP TESTS                                                                              INCOME                                                                             POP  STAND                                                                             ROOTS                                                                             TEST                                   BRAND  PRODUCT                                                                             YIELD                                                                             MOIST                                                                             /ACRE                                                                              K/ACRE                                                                             (%) (%) WT                                     __________________________________________________________________________    PIONEER                                                                              3730  164.5                                                                             22.3                                                                              330.06                                                                             25.0 95  100 54.9                                   PIONEER                                                                              3737  158.4                                                                             20.6                                                                              323.05                                                                             24.1 94  100 54.9                                   Advantage    6.1 -1.7                                                                              7.01 0.9  1   0   0.0                                    #Comparisons 13  13  13   9    5   3   13                                     Percent Wins 76  7   61   66   40  0   38                                     Prob. of Diff.                                                                             97  99  76   87   16  0   2                                      PIONEER                                                                              3730  155.5                                                                             23.4                                                                              309.06                                                                             27.3 93  99  56.0                                   PIONEER                                                                              3723  153.8                                                                             22.2                                                                              309.43                                                                             27.7 93  99  56.1                                   Advantage    1.7 -1.2                                                                              -0.37                                                                              -0.4 0   0   -0.1                                   #Comparisons 56  56  56   36   27  17  48                                     Percent Wins 53  17  51   27   29  5   45                                     Prob. of Diff.                                                                             79  99  12   73   45  29  10                                     PIONEER                                                                              3730  163.1                                                                             20.9                                                                              331.68                                                                             24.8 93  95  55.8                                   PIONEER                                                                              3733  159.2                                                                             20.3                                                                              326.13                                                                             24.8 85  96  57.9                                   Advantage    3.9 -0.6                                                                              5.55 0.0  8   -1  -2.1                                   #Comparisons 307 307 307  193  155 116 291                                    Percent Wins 63  30  60   40   56  13  3                                      Prob. of Diff.                                                                             99  99  99   17   99  15  99                                     PIONEER                                                                              3730  171.9                                                                             17.1                                                                              362.71                                                                             28.0 87  100 57.4                                   PIONEER                                                                              3714  165.1                                                                             16.8                                                                              348.91                                                                             27.4 90  100 57.1                                   Advantage    6.8 -0.3                                                                              13.80                                                                              0.6  -3  0   0.3                                    #Comparisons 17  17  17   13   6   4   17                                     Percent Wins 70  52  76   46   33  0   52                                     Prob. of Diff.                                                                             97  79  96   72   45  0   82                                     PIONEER                                                                              3730  172.2                                                                             19.6                                                                              354.67                                                                             25.4 93  93  56.2                                   PIONEER                                                                              3563  171.7                                                                             20.5                                                                              351.21                                                                             25.5 91  94  56.9                                   Advantage    0.5 0.9 3.46 -0.1 2   -1  -0.7                                   #Comparisons 321 321 321  218  159 128 299                                    PercentWins  53  74  58   44   46  12  14                                     Prob. of Diff.                                                                             54  99  98   9    98  44  99                                     PIONEER                                                                              3730  166.8                                                                             20.5                                                                              340.95                                                                             25.4 93  95  56.0                                   Weighted Avg 164.5                                                                             20.5                                                                              336.58                                                                             25.4 88  95  57.2                                   Advantage    2.3 0.0 4.37 0.0  5   0   -1.2                                   #Comparisons 714 714 714  469  352 268 668                                    Percent Wins 58  49  59   42   49  12  13                                     Prob. of Diff.                                                                             99  5   99   18   99  36  99                                     __________________________________________________________________________     Note: The probability values are useful in analyzing if there is a real       difference in the genetic potential of the products involved. High values     are desirable, with 95% considered significant for real differences.     

Comparison of Key Characteristics for Hybrid 3730

Characteristics of Pioneer Hybrid 3730 are compared to Pioneer Hybrids3737, 3723, 3733, 3714 and 3563 in Table 4. The values given for most ofthe traits are on a 1-9 basis. In these cases 9 would be outstanding,while 1 would be poor for the given characteristics. These values arebased on performance of a given hybrid relative to other Pioneercommercial, precommercial and competitive hybrids that are grown inresearch and strip test trials. These performance based values aredetermined utilizing several factors such as research data, experiencethe trained corn researchers had in the field, and sales experience withthe hybrids in strip tests and the field. These values reflect thehybrid's relative performance to other hybrids for the characteristicslisted. Table 4 shows Hybrid 3730 yielded well for its maturity,especially in high population density conditions. Hybrid 3730 has gooddrydown and early growth when compared to the other hybrids. Hybrid 3730has overall high yield and other good agronomic characteristics whichshould make it an important hybrid in its area of adaptation.

                                      TABLE 4                                     __________________________________________________________________________    Hybrid Patent Comparisons-Characteristics                                     Pioneer Hybrid 3730 vs. Pioneer Hybrids 3737, 3723, 3733, 3714 and            __________________________________________________________________________    3563                                                                                    SILK                                                                              PHY GDU GDU     H/  L/                                          VARIETY                                                                             CRM CRM CRM SILK                                                                              PHY YLD POP POP D/D S/L R/L                             __________________________________________________________________________    3730  99  99  100 1230                                                                              2390                                                                              9   9   7   8   6   6                               3737  98  98      1210    7   7   7   7   4   5                               3723  99  101 100 1260                                                                              2390                                                                              7   7   8   6   6   5                               3733  99  101 101 1260                                                                              2420                                                                              7   6   7   6   4   6                               3714  100 102     1260    7   7   6   7   5   4                               3563  103 107 105 1330                                                                              2530                                                                              8   8   7   6   6   6                               __________________________________________________________________________          STA     TST         PLT EAR     BRT                                     VARIETY                                                                             GRN D/T WT  G/A E/G HT  HT  D/E STK PRO P/Y                             __________________________________________________________________________    3730  6   7   5   6   9   7   5   6   4   5   9                               3737  4   8   4   4   5   5   4   4   5   5   7                               3723  6   6   5   5   3   7   8   5   3   6   8                               3733  7   7   8   7   5   6   6   6   7   5   7                               3714  5   5   5   5   4   5   7   5   5   5   7                               3563  6   7   8   6   4   7   4   7   5   4   7                               __________________________________________________________________________

INDUSTRIAL APPLICABILITY

This invention includes hybrid maize seed of 3730 and the hybrid maizeplant produced therefrom. The foregoing was set forth by way of exampleand is not intended to limit the scope of the invention.

As used herein, the term plant includes plant cells, plant protoplasts,plant cell tissue cultures from which maize plants can be regenerated,plant calli, plant clumps, and plant cells that are intact in plants, orparts of plants, such as embryos, pollen, ovules, flowers, kernels,ears, cobs, leaves, seeds, husks, stalks, roots, root tips, anthers,silk and the like.

Duncan, Williams, Zehr, and Widholm, Planta, (1985) 165:322-332 reflectsthat 97% of the plants cultured which produced callus were capable ofplant regeneration. Subsequent experiments with both inbreds and hybridsproduced 91% regenerable callus which produced plants. In a furtherstudy in 1988, Songstad, Duncan & Widholm in Plant Cell Reports (1988),7:262-265 reports several media additions which enhance regenerabilityof callus of two inbred lines. Other published reports also indicatedthat "hontraditional" tissues are capable of producing somaticembryogenesis and plant regeneration. K. P. Rao, et al., Maize GeneticsCooperation Newsletter, 60:64-65 (1986), refers to somatic embryogenesisfrom glume callus cultures and B. V. Conger, et al., Plant Cell Reports,6:345-347 (1987) indicates somatic embryogenesis from the tissuecultures of maize leaf segments. Thus, it is clear from the literaturethat the state of the art is such that these methods of obtaining plantsare, and were, "conventional" in the sense that they are routinely usedand have a very high rate of success.

Tissue culture of maize is described in European Patent Application,publication 160,390, incorporated herein by reference. Maize tissueculture procedures are also described in Green and Rhodes, "PlantRegeneration in Tissue Culture of Maize," Maize for Biological Research(Plant Molecular Biology Association, Charlottesville, Va. 1982, at367-372) and in Duncan, et al., "The Production of Callus Capable ofPlant Regeneration from Immature Embryos of Numerous Zea MaysGeneotypes," 165 Planta 322-332 (1985). Thus, another aspect of thisinvention is to provide cells which upon growth and differentiationproduce maize plants having the genotype of 3730.

Maize is used as human food, livestock feed, and as raw material inindustry. The food uses of maize, in addition to human consumption ofmaize kernels, include both products of dry- and wet-milling industries.

Maize, including both grain and non-grain portions of the plant, is alsoused extensively as livestock feed, primarily for beef cattle, dairycattle, hogs, and poultry.

Industrial uses of maize include production of ethanol, maize starch inthe wet-milling industry and maize flour in the dry-milling industry.The industrial applications of maize starch and flour are based onfunctional properties, such as viscosity, film formation, adhesiveproperties, and ability to suspend particles. The maize starch and flourhave application in the paper and textile industries. Other industrialuses include applications in adhesives, building materials, foundrybinders, laundry starches, explosives, oil-well muds, and other miningapplications.

Plant parts other than the grain of maize are also used in industry.Stalks and husks are made into paper and wallboard and cobs are used forfuel and to make charcoal.

The seed of the hybrid maize plant and various parts of the hybrid maizeplant can be utilized for human food, livestock feed, and as a rawmaterial in industry.

Although the foregoing invention has been described in some detail byway of illustration and example for purposes of clarity andunderstanding, it will be obvious that certain changes and modificationsmay be practiced within the scope of the invention, as limited only bythe scope of the appended claims.

Applicant has made a deposit of at least 2,500 seeds of Hybird MaizeSeed 3730 with the American Type Culture Collection (ATCC), Rockville,Md. 20852 USA, ATCC Deposit No. 209127. The seeds deposited with theATCC on Jun. 23, 1997, were taken from the deposit maintained by PioneerHi-Bred International, Inc., 700 Capital Square, 400 Locust Street, DesMoines, Iowa 50309-2340 since prior to the filing date of thisapplication. This deposit of the Hybird Maize Seed 3730 will bemaintained in the ATCC depository, which is a public depository, for aperiod of 30 years, or 5 years after the most recent request, or for theenforceable life of the patent, whichever is longer, and will bereplaced if it becomes nonviable during that period. Additionally,Applicant has satisfied all the requirements of 37 C.F.R. §§1.801-1.809,including providing an indication of the viability of the sample.Applicant imposes no restrictions on the availability of the depositedmaterial from the ATCC; however. Applicant has no authority to waive anyrestrictions imposed by law on the transfer of biological material orits transportation in commerce. Applicant does not waive anyinfringement of its rights granted under this patent.

What is claimed is:
 1. A hybrid maize plant designated 3730 and itsparts, representative seed capable of producing said hybrid maizeplanting having ATCC accession number
 209127. 2. Pollen of the plant ofclaim
 1. 3. An ovule of the plant of claim
 1. 4. A tissue of regenerablecells of a hybrid maize plant designated 3730, representative seed saidhybrid maize plant having ATCC accession number 209127, wherein thetissue regenerates plants capable of expressing all the morphologicaland physiological characteristics of hybrid maize plant
 3730. 5. Atissue culture according to claim 4, the tissue culture selected fromthe group consisting of leaves, pollen, embryos, roots, root tips,anthem, silks, flowers, kemels, ears, cobs, husks, stalks, and cells,and protoplasts thereof.
 6. A maize plant regenerated from the tissueculture of claim 4, and capable of expressing all the morphological andphysiological characteristics of hybird maize plant 3730.